The invention relates to a manual grinder of the species defined in the preamble of claim 1, in particular to grind spices such as pepper and salt, coffee beans, grains, herbs etc.
The designs of known manual grinders (German patents 27 47 059; 28 18 216 and 36 90 785; U.S. Pat. No. 2,782,998; French patent 842 769 and Austrian patent 179 958) may be loosely described as follows:
A cylindrical, vertically configured container holding the material to be ground is received in a grinder housing. The set of grinding elements is located at the bottom and consists of a stationary grinding ring and a rotatable grinding cone. The grinding cone is affixed to the lower end of the drive shaft which runs vertically at the center of the container. The drive grip or crank is affixed to the upper end of the drive shaft. The grinding gap and hence the grinding granularity is adjusted by a screw-nut at one of the ends of the drive shaft. As regards spice grinders of earlier times, the grinding cone is kept in position by a dedicated screw.
The spice grinders of the known designs incur the following drawbacks:
It is impossible to accurately adjust the grinding gap in controlled and functional manner and therefore it is impossible to adjust the grinding granularity in simple, practical and effective manner. In some known grinders, the adjustment of the grinding gap requires a screwdriver and a wrench. In the process, the grinder must be kept between the knees or be held by another person. On this light the modern design using an adjusting screw at the top of a rotary handle would appear advantageous because the user can implement the adjustment merely using his/her hands. However difficulties arise in practice because this screw significantly hampers grinder operation. It is known to circumvent these drawbacks by appropriately shaping the screw, for instance making it flat, however also making it difficult to use it, or to mask it into a recess in the rotating grip, whereby however operation is also made significantly more difficult. In some manual grinders the screw-nut is hidden underneath the grinding unit, where it is even more cumbersome to reach and adjust.
If the grinder is desired to grind very finely, the screw must be tightened rather hard. As a rule the known grinders are without a scale or a visible adjustment stop. As a result, the adjusting nut often is excessively tightened. In such a case, it can hardly be rotated or it locks altogether. There is danger of damaging the set of grinding elements. Another drawback is that undesired, autonomous resetting of the screw nut cannot be fully precluded. This nut might draw tighter itself in the case of a well tensioned grinder, or it may further loosen if this grinder is adjusted loosely.
Container filling is laborious in the known manual grinders. The known containers must be laboriously screwed apart to allow filling and then be reassembled to become operational again.
Some manual grinders also can be filled through a side aperture. However this aperture is so small and difficult to access that for instance peppercorns must be loaded individually.
Furthermore the known grinders entail complex and laborious operation. The various functions such as filling, grinding and adjusting granularity are frequently not immediately recognized by the user. The grinders are xe2x80x9cdirtyxe2x80x9d because a residue of the ground material stays behind on account of the grinder components at the bottom of the grinder or around the set of grinding elements and will drop on the support surface when the grinder is no longer used.
The objective of the present invention is to so improve a manual grinder of the initially cited kind that the above discussed drawbacks of the known grinders shall be precluded.
This problem is solved by the invention by the features of claim 1.
Advantageous and appropriate further developments are stated in the dependent claims.
In the invention, the grinding unit is sealed per se and fitted with an integrated grinding-gap adjusting device. This grinding unit is driven by a flexible shaft. The grinder shaft and the shaft of the drive grip may be mounted at a mutual angle.
In the design of the manual grinder of the invention, a grip to actuate the grinder is mounted to a side of the grinder housing and drives the grinding unit by means of the flexible shaft. The design of the invention improves significantly the functionality and handling of the manual grinder. At the top, previously reserved for the rotary grip or crank of the known manual grinders, there is now a large aperture which can be easily closed by a lid and which allows filling the container in problem-free manner. The manual grinder of the invention no longer requires being disassembled for filling. The granularity adjusting device of the invention is driven by an easily handled lever. This lever projects from a horizontal slot out of the grinder housing and illustratively can be moved through 120xc2x0, and optionally there may be a continuous range of adjustments or also three discrete adjustment positions for fine, medium and coarse granularities.
Markings may be used for such purposes on the housing. The range of lever rotation may be selected so it be out of the way when holding the grinder.
The functions and purposes of the operating components of the grinder of the invention are immediately recognizable. Any person at once understands where the rotary grip is located, where the grinder will be filled and how to adjust granularity.
The grinder of the invention allows grinding rapidly and effortlessly both small and large quantities of material because the rotary grip can be driven rapidly and effectively without fatigue, while also allowing slow and well controlled grinding. The grinder of the invention can be held as well as actuated ergonomically, in simple and convenient manner.
Lastly the manual grinder of the invention is also xe2x80x9ccleanxe2x80x9d, that is, it will hardly leave behind grinding residues when being set down. This feature is achieved in that the components which in the conventional designs are in the vicinity of the discharge aperture and which temporarily retain ground particles, are superfluous in the design of the invention and therefore are absent from the design of the invention.
The invention is elucidated below in relation to the attached drawing shown illustrative embodiments.